Configuring a multicast or broadcast wireless network

ABSTRACT

A wireless network architecture for providing Multicast-Broadcast over a Single Frequency Network (MBSFN) messages is disclosed. A network element may use an interface to communicate with a cluster of network elements. The network element may multicast an MBSFN message to a cluster and may determine when to retransmit the MBSFN message if an acknowledgement message is not received.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.12/169,563, filed Jul. 8, 2008, which is incorporated by reference as iffully set forth.

FIELD

The field of the invention relates generally to cellular communication.More particularly, the field of the invention relates to a method andapparatus for providing cell configuration information to a networkelement.

BACKGROUND

In a typical cellular network, such as a Universal Terrestrial RadioAccess-Time Division Duplex (UTRA-TDD) network, a Radio NetworkController (RNC) is responsible for the configuration of a set of cells.The configuration of the cells is typically achieved using astandardised protocol, such as the 3GPP (3rd Generation PartnershipProject) Node-B Application Part (NBAP) of the Iub interface. Theimplementation of the configuration of a cell from its RNC inconventional network architecture is based on a point-to-pointconnection from the RNC to each individual cell.

As will be appreciated by a skilled artisan, the network resourceswithin a cellular network are limited, and as such any reduction of thesignalling message flow and content between network elements isdesirable. Furthermore, any reduction in the workload of the processingresources of RNCs, and the amount of time taken to reconfigure cells isalso desirable.

Thus, there exists a continual need for improved methods and techniquesfor providing cell configuration information to network elements.

SUMMARY

Accordingly, embodiments of the invention seek to mitigate, alleviate oreliminate one or more of the abovementioned disadvantages singly or inany combination.

According to a first aspect of the invention, there is provided anetwork controller for supporting a multi-cell service in a cellularcommunication network. The network controller comprises an interfaceconnection that is operably coupled to at least one network elementsupporting communication within a communication cell of thecommunication network. The network controller comprises signalprocessing logic for generating a cell configuration message comprisingcell configuration information. Transmitting logic is for transmittingthe cell configuration message to the at least one network element usinga multicast protocol.

Thus, embodiments of the invention may allow a network controller todeliver cell configuration information to a plurality of networkelements substantially simultaneously, with a single transmission. As aresult, the bandwidth needed at the network controller end of aninterface between the network controller and the network elements may besignificantly reduced, along with the processing load for the networkcontroller in relation to the provision of cell configurationinformation to the network elements. Furthermore, since cellconfiguration information may be transmitted substantiallysimultaneously to all of the network elements, the time needed toreconfigure a plurality of cells may be significantly reduced, inparticular when a large number of cells need to be reconfigured.

According to optional features of the invention, the cellularcommunication network may comprise a plurality of communication cellclusters, and each cell cluster in turn comprises a plurality ofcommunication cells, such that the transmitting logic may be furtheroperable to transmit the cell configuration message to a plurality ofnetwork elements within a communication cell cluster. In this manner,the multicast transmission of cell reconfiguration information may bebroadcast to multiple network elements.

According to optional features of the invention, the multicast protocolmay comprise the Internet Group Management Protocol (IMGP), and thenetwork controller may transmit the cell configuration message using aStream Control Transmission Protocol (SCTP).

According to a further optional feature of the invention, the cellconfiguration information may comprise one or more from a group of:

(i) Common Physical CHannel (CPCH) configuration information;

(ii) Forward Access CHannel (FACH) configuration information;

(iii) Paging CHannel (PCH) configuration information;

(iv) Paging Indicator CHannel (PICH) configuration information;

(v) MBMS paging Indicator CHannel (MICH) configuration information;

(vi) timeslot configuration information;

(vii) Packet Random Access CHannel (PRACH) configuration information;

(viii) Random Access CHannel (RACH) configuration information; and

(ix) Fast Physical Access CHannel (FPACH) configuration information.

According to a further optional feature of the invention, the networkcontroller may comprise enabling logic operable to enable the at leastone network element to subscribe to a multi-cell service by, forexample, way of the Internet Group Management Protocol (IGMP).

According to an optional feature of the invention, the networkcontroller may comprise a first receiving logic operable to receive viaa unicast protocol an acknowledgement messages from at least one networkelement, and acknowledge receipt of cell configuration information.

According to an optional feature of the invention, the signal processinglogic may be further operable, upon failure to receive anacknowledgement message from a network element subscribed to amulti-cell service following transmission of cell configurationinformation using the multicast protocol, to re-transmit theconfiguration information to the network element from which anacknowledgement message was failed to be received, using a unicastprotocol. Optionally, the unicast protocol may comprise an InternetProtocol (IP).

According to an optional feature of the invention, the networkcontroller may comprise address logic operable to use a substantiallyunique multicast address for signalling purposes, at least with respectto other network controllers within the communication network.

According to a second aspect of the invention, there is provided anetwork element for supporting communication within a communication cellof a cellular communication network. The network element comprises areceive logic module for to receiving cell configuration information forproviding a multi-cell service from a network controller using amulticast protocol.

According to a third aspect of the invention, there is provided a methodfor providing cell configuration information for a multi-cell service toa network element supporting communication within a communication cellof a communication network. The method comprises the steps of generatinga cell configuration message comprising cell configuration informationfor providing a multi-cell service, and transmitting the cellconfiguration message to the at least one network element using amulticast protocol.

According to a fourth aspect of the invention, there is provided acellular communication system comprising a network controller adapted tosupport the abovementioned method for providing cell configurationinformation for a multi-cell service to a network element.

According to a fifth aspect of the invention, there is provided anintegrated circuit for supporting multimedia broadcast communicationsover a communication system, the integrated circuit comprising messagegeneration logic for generating a cell configuration message comprisingcell configuration information for providing a multi-cell service; and atransmitting logic for transmitting the cell configuration message to atleast one network element using a multicast protocol.

According to a sixth aspect of the invention, there is provided acomputer-readable medium having executable program code, for programmingsignal processing logic to perform the abovementioned method forproviding cell configuration information for a multi-cell service to anetwork element.

These and other aspects, features and advantages of the invention willbe apparent from, and elucidated with reference to, the embodimentsdescribed hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention will be described, by way of example only,with reference to the accompanying drawings, in which:

FIG. 1 illustrates an example of a block diagram of part of a cellularcommunication system.

FIG. 2 illustrates an example of an RNC adapted according to embodimentsof the invention.

FIG. 3 illustrates an example of a simplified signalling diagram for theRNC of FIG. 2 according to embodiments of the invention.

FIG. 4 illustrates an example of a simplified flowchart of a method ofproviding cell configuration information for a multi-cell serviceaccording to embodiments of the invention.

FIG. 5 illustrates a typical computing system that may be employed toimplement processing functionality in embodiments of the invention.

DESCRIPTION OF EMBODIMENTS OF THE INVENTION

The demand for multimedia services that can be received via mobilecommunication devices, such as mobile telephone handsets and otherhandheld devices, is expected to grow rapidly. One technology fordelivering multimedia broadcast services over cellular communicationnetworks is the Multimedia Broadcast and Multicast Service (MBMS)developed by the 3rd Generation Partnership Project (www.3gpp.com).

A particular variant of MBMS comprises a network operating in abroadcast only mode for Multicast/Broadcast over a single FrequencyNetwork (MBSFN). In such a dedicated broadcast cellular network, allcells involved in the broadcast of a service will have an identicalconfiguration of the physical resources used for that service. Inessence, all cells involved in the broadcast of the service will beconfigured to transmit an identical and time synchronous waveform forthat service.

Embodiments of the invention will be described in a context of aUniversal Mobile Telecommunications System (UMTS) Terrestrial RadioAccess Network (UTRAN) system. However, it will be appreciated thatembodiments of the invention are not limited to a UTRAN system, but maybe implemented within alternative cell-based communication systems, forexample a WiMAX (Worldwide Interoperability for Microwave ACceSS)network system, with which multiple communications cells are to beprovided with substantially the same configuration information.

Referring now to FIG. 1, there is illustrated an example of a blockdiagram of part of a cellular communication system 100, which for theillustrated embodiments comprise a part of a UTRAN system. The system100 comprises a network controller, which for the illustratedembodiments are in a form of a Radio Network Controller (RNC) 110. TheRNC 110 is operably coupled to one or more network elements forsupporting communication within respective communication cells 130 ofthe communication network 120. For the illustrated embodiments, thenetwork elements are in a form of wireless base stations, referred to in3GPP parlance as Node-Bs 125, and the RNC 110 is operably coupled to theNode-Bs 125 via an Iub interface 105.

For completeness, the RNC 110 of FIG. 1 is further operably coupled to aServing General Packet Radio System (GPRS) Support Node (SGSN) 150 viaIuPS interface, as shown.

In accordance with embodiments of the invention, the communicationnetwork 120 of FIG. 1 may be configured to deliver multi-cell servicesto mobile communication devices, such as User Equipment (UE) 145,located within the communication cells 130, via an air interface Uu 135.For example, a multi-cell service may comprise a broadcast service thatmay be provided to wireless communication devices over the communicationnetwork 120 via Node-Bs. In particular, the communication network 120 ofFIG. 1 may be configured to operate in a broadcast only mode forMulticast/Broadcast over a single Frequency Network (MBSFN). In thismanner, each individual communication cell 130 may form a part of acluster of communication cells 140, a cluster defining a subset of thecommunication cells 130 within the system 100, or all of thecommunication cells 130 within the system 100. Multi-cell services suchas broadcast services may then be transmitted substantiallysimultaneously using identical physical resources by all communicationcells 130 of a cluster 140.

Referring now to FIG. 2, there is illustrated an example of an RNC 210adapted according to embodiments of the invention, operably coupled toNode-Bs 220, 230, 240 via an Iub interface 205. The RNC 210 comprisessignal processing logic module 212 and memory element 215. Similarly,each of the Node-Bs 220, 230, 240 comprises signal processing logicmodule 222, 232, 242 and memory element 225, 235, 245 respectively.

In accordance with embodiments of the invention, the signal processinglogic module 212 of the RNC 210 is operable to generate a cellconfiguration message comprising cell configuration information forproviding a multi-cell service, and to transmit the cell configurationmessage to the Node-Bs 220, 230, 240 using a multicast protocol.

In this manner, the RNC 210 is able to deliver the configurationinformation to a plurality of Node-Bs, for example all Node-Bs 220, 230,240 within a cluster 250 substantially simultaneously, within a singletransmission. As a result, the bandwidth needed at the RNC end of theIub interface 205 may be significantly reduced, along with theprocessing load for the RNC 210 in relation to the provision of cellconfiguration information to the Node-Bs 220, 230, 240. Furthermore,since cell configuration information may be transmitted substantiallysimultaneously to all of the Node-Bs 220, 230, 240 within the cluster250, the time needed to reconfigure a plurality of cells may besignificantly reduced, in particular when a large number of cells needto be reconfigured. By way of example, a configuration message maycomprise 400 bytes, and an acknowledgement message may comprise 50bytes. Configuring 50 cells within a cluster using the prior art methodof individually sending configuration messages to each cell using aunicast protocol would use 50×400 bytes for the configuration messages,and 50×50 bytes for the acknowledgement messages (assuming no need forretransmissions). Thus, using the prior art method, a total of 22500bytes are transmitted. However, configuring the 50 cells within thecluster using a multicast protocol in accordance with examples of thepresent invention would only use a single 400 bytes configurationmessage. Accordingly, a total of only 2900 bytes would be required to betransmitted, a reduction by a factor of approximately eight in thenumber of bytes transmitted.

The RNC 210 may be operable to use any suitable multicast protocol totransmit the cell configuration information. For example, the RNC 210may use a packet-based multicast protocol such as the Internet GroupManagement Protocol (IGMP). In this manner, all Node-Bs 220, 230, 240providing a particular multi-cell service may be configured to join theappropriate multicast group corresponding to that multi-cell service.

As will be appreciated by a skilled artisan, there are several versionsof IGMP, as defined by RFC (Request for Comments) documents of the IETF(Internet Engineering Task Force). IGMP v1 is defined by RFC 1112, IGMPv2 is defined by RFC 2236, and IGMP v3 is defined by RFC 3376.

The RNC 210 may be further operable to transmit the cell configurationmessage using a variant of a Stream Control Transmission Protocol(SCTP). As will be appreciated by a skilled artisan, SCTP is transportlayer protocol developed by the IETF (Internet Engineering Task Force)Signalling Transport working group, and defined in RFC 4960, and whichis traditionally related to one IP address and one port. SCTP isgenerally accepted as being a faster, more reliable protocol than, say,TCP (Transport Control Protocol). Furthermore, SCTP does not requireacknowledgement messages to be provided at the NBAP (Node-B ApplicationPart) level, as is the case for UDP (User Datagram Protocol).Accordingly, a variant of SCTP relating to both a multicast IP addressand port and a unicast IP address and port may be utilised. In thismanner, an SCTP downlink may be employed via the multicast address andport, whilst the uplink may be employed via the unicast address andport.

The cell configuration information may comprise any information thatenables a Node-B to be configured to provide a multi-cell service tomobile communications devices within its respective cell. For example,the cell configuration information may comprise one or more from a groupof:

(i) Common Physical CHannel (CPCH) configuration information;

(ii) Forward Access CHannel (FACH) configuration information;

(iii) Paging CHannel (PCH) configuration information;

(iv) Paging Indicator CHannel (PICH) configuration information;

(v) MBMS paging Indicator CHannel (MICH) configuration information;

(vi) timeslot configuration information;

(vii) Packet Random Access CHannel (PRACH) configuration information;

(viii) Random Access CHannel (RACH) configuration information; and

(ix) Fast Physical Access CHannel (FPACH) configuration information.

Referring now to FIG. 3, there is illustrated an example of a simplifiedsignalling diagram 300 for the RNC 210 of FIG. 2 to provide cellconfiguration information, for providing a multi-cell service, to theNode-Bs 220, 230, 240.

As previously mentioned, the RNC 210 is operable to generate a cellconfiguration message comprising cell configuration information forproviding a multi-cell service, and to transmit the cell configurationmessage to the Node-Bs 220, 230, 240 using a multicast protocol.Accordingly, the RNC 210 transmits the cell configuration message 310substantially simultaneously to all of the Node-Bs 220, 230, 240 using amulticast protocol. Upon receipt of the cell configuration message 310,the Node-Bs 220, 230 respond by transmitting acknowledgement messages320, 330 back to the RNC 210 using a unicast protocol, acknowledgingreceipt of the cell configuration message. As will be appreciated by askilled artisan, acknowledgement messages may be transmitted at anyappropriate level, for example at the SCTP level or at the NBAP level.

For the example illustrated in FIG. 3, the RNC 210 fails to receive anacknowledgement message from one of the Node-Bs, Node-B_(—)3 240, asillustrated by box 340. Accordingly, upon failure to receive anacknowledgement message from Node-B_(—)3 240, the RNC 210, or morespecifically for the embodiments illustrated in FIG. 2 the signalprocessing logic module 212 thereof is operable to retransmit theconfiguration information to Node-B_(—)3 240 from which anacknowledgement message was failed to be received. The signal processinglogic module 212 may retransmit the configuration information toNode-B_(—)3 240 using a unicast protocol 350, for example a packet-basedunicast protocol such as a unicast IP protocol. By way of example, thesignal processing logic module 212 may simply re-transmit the cellconfiguration message originally generated for multicast transmission.Alternatively, the signal processing logic module 212 may generate a newcell configuration message, comprising the cell configurationinformation, specifically for re-transmission using a unicast protocolto the, or each, Node-B from which an acknowledgement message was notreceived. Upon receipt of the cell configuration message 350, the Node-B240 responds by transmitting acknowledgement messages 360 back to theRNC 210 using a unicast protocol, acknowledging receipt of the cellconfiguration message.

In this manner, the RNC 210 only resorts to unicast, point-to-pointsignalling for Node-Bs that fails to acknowledge receipt of the initialmulticast message. Thus, depending upon the probability of packet lossover the Iub interface 205, the net result will typically be an overallreduction in the amount of traffic generated for any reconfiguration ofthe network resources and a shortening of the reconfiguration period.

Alternatively, where acknowledgement messages fail to be received from aplurality of Node-Bs, the signal processing logic module 212 mayretransmit the configuration information to the Node-Bs using amulticast protocol, in order to again minimise the number oftransmissions needed to be made by the signal processing logic module212. In particular, the signal processing logic module 212 may determinewhether to retransmit the configuration information using a unicast ormulticast protocol based on a trade-off between the number of unicastconfiguration information messages that the signal processing logicmodule would need to transmit, and the number of unnecessaryacknowledgement messages that would result from a multicastconfiguration information message.

In accordance with embodiments of the invention, and in a system withmultiple RNCs, each RNC may use a substantially unique multicast addressfor signalling purposes, at least with respect to other networkcontrollers within the communication network. In this manner, Node-Bsmay be controlled by a specific RNC through configuration of the controlplane multicast subscription information of the Node-Bs.

Referring now to FIG. 4, there is illustrated an example of a simplifiedflowchart 400 of a method for providing cell configuration informationfor a multi-cell service, for example a broadcast service, to a networkelement supporting communication within a communication cell of acommunication network according to embodiments of the invention. Forexample, the method of FIG. 4 may be implemented in the form ofcomputer-readable code stored within, say, the memory element 215 of RNC210 of FIG. 2, for programming the signal processing logic module 212 toperform the method.

The method starts at step 410, and moves to step 420, with thegeneration of a cell configuration message comprising cell configurationinformation for providing a cell multi-cell service. Next, in step 430,the cell configuration message is transmitted using a multicast protocolto one or more Node-Bs.

If acknowledgement messages are not received from all of the Node-Bssubscribed to the relevant multicast group in step 440, the method moveson to step 450, where it is determined whether to retransmit theconfiguration information using the multicast protocol, or tore-transmit the configuration information using a unicast protocol. Forexample, it may be determined whether to re-transmit the configurationinformation using a unicast or multicast protocol based on a trade-offbetween the number of unicast configuration information messages thatwould need to transmitted to the unacknowledged Node-Bs, and the numberof unnecessary acknowledgement messages that would result from amulticast configuration information message.

If it is determined to re-transmit the configuration information using aunicast protocol, the method moves to step 460, where the cellconfiguration message is re-transmitted to those Node-Bs from whichacknowledgement messages have not been received, using a unicastprotocol. The method then loops back to step 440.

If it is determined to re-transmit the configuration information using amulticast protocol, the method moves to step 470, where the cellconfiguration message is re-transmitted to, for example all of the oneor more Node-Bs, using a multicast protocol. The method then loops backto step 440.

Once acknowledgement messages have been received from all of the Node-Bssubscribed to the relevant multicast group, the method ends, at step480.

FIG. 5 illustrates a typical computing system 500 that may be employedto implement processing functionality in embodiments of the invention.Computing systems of this type may be used in a network controller orother network element (which may be an integrated device, such as amobile phone or a USB/PCMCIA modem), for example. Those skilled in therelevant art will also recognize how to implement the invention usingother computer systems or architectures. Computing system 500 mayrepresent, for example, a desktop, laptop or notebook computer,hand-held computing device (PDA, cell phone, palmtop, etc.), mainframe,server, client, or any other type of special or general purposecomputing device as may be desirable or appropriate for a givenapplication or environment. Computing system 500 can include one or moreprocessors, such as a processor 504. Processor 504 can be implementedusing a general or special purpose processing engine such as, forexample, a microprocessor, microcontroller or other control logic. Inthis example, processor 504 is connected to a bus 502 or othercommunications medium.

Computing system 500 can also include a main memory 508, such as randomaccess memory (RAM) or other dynamic memory, for storing information andinstructions to be executed by processor 504. Main memory 508 also maybe used for storing temporary variables or other intermediateinformation during execution of instructions to be executed by processor504. Computing system 500 may likewise include a read only memory (ROM)or other static storage device coupled to bus 502 for storing staticinformation and instructions for processor 504.

The computing system 500 may also include information storage system510, which may include, for example, a media drive 512 and a removablestorage interface 520. The media drive 512 may include a drive or othermechanism to support fixed or removable storage media, such as a harddisk drive, a floppy disk drive, a magnetic tape drive, an optical diskdrive, a compact disc (CD) or digital video drive (DVD) read or writedrive (R or RW), or other removable or fixed media drive. Storage media518 may include, for example, a hard disk, floppy disk, magnetic tape,optical disk, CD or DVD, or other fixed or removable medium that is readby and written to by media drive 512. As these examples illustrate, thestorage media 518 may include a computer-readable storage medium havingstored therein particular computer software or data.

In alternative embodiments, information storage system 510 may includeother similar components for allowing computer programs or otherinstructions or data to be loaded into computing system 500. Suchcomponents may include, for example, a removable storage unit 522 and aninterface 520, such as a program cartridge and cartridge interface, aremovable memory (for example, a flash memory or other removable memorymodule) and memory slot, and other removable storage units 522 andinterfaces 520 that allow software and data to be transferred from theremovable storage unit 522 to computing system 500.

Computing system 500 can also include a communications interface 524.Communications interface 524 can be used to allow software and data tobe transferred between computing system 500 and external devices.Examples of communications interface 524 can include a modem, a networkinterface (such as an Ethernet or other NIC card), a communications port(such as for example, a universal serial bus (USB) port), a PCMCIA slotand card, etc. Software and data transferred via communicationsinterface 524 are in the form of signals which can be electronic,electromagnetic, and optical or other signals capable of being receivedby communications interface 524. These signals are provided tocommunications interface 524 via a channel 528. This channel 528 maycarry signals and may be implemented using a wireless medium, wire orcable, fiber optics, or other communications medium. Some examples of achannel include a phone line, a cellular phone link, an RF link, anetwork interface, a local or wide area network, and othercommunications channels.

In this document, the terms ‘computer program product’‘computer-readable medium’ and the like may be used generally to referto media such as, for example, memory 508, storage device 518, orstorage unit 522. These and other forms of computer-readable media maystore one or more instructions for use by processor 504, to cause theprocessor to perform specified operations. Such instructions, generallyreferred to as ‘computer program code’ (which may be grouped in the formof computer programs or other groupings), when executed, enable thecomputing system 500 to perform functions of embodiments of the presentinvention. Note that the code may directly cause the processor toperform specified operations, be compiled to do so, and/or be combinedwith other software, hardware, and/or firmware elements (e.g., librariesfor performing standard functions) to do so.

In an embodiment where the elements are implemented using software, thesoftware may be stored in a computer-readable medium and loaded intocomputing system 500 using, for example, removable storage drive 522,drive 512 or communications interface 524. The control logic module (inthis example, software instructions or computer program code), whenexecuted by the processor 504, causes the processor 504 to perform thefunctions of the invention as described herein.

It will be appreciated that, for clarity purposes, the above descriptionhas described embodiments of the invention with reference to generalfunctional units and processors. However, it will be apparent that anysuitable distribution of functionality between different functionalunits, processors or domains may be used without detracting from theinvention. For example, functionality illustrated to be performed by asignal processing logic module may be performed by separate processorsor controllers, or may be performed by the same processor or controller.Hence, references to specific functional units are only to be seen asreferences to suitable means for providing the described functionality,rather than indicative of a strict logical or physical structure ororganization.

Aspects of the invention may be implemented in any suitable formincluding hardware, software, firmware or any combination of these. Theinvention may optionally be implemented, at least partly, as computersoftware running on one or more data processors and/or digital signalprocessors. Thus, the elements and components of an embodiment of theinvention may be physically, functionally and logically implemented inany suitable way. Indeed, the functionality may be implemented in asingle unit, in a plurality of units or as part of other functionalunits.

Although the invention has been described in connection with someembodiments, it is not intended to be limited to the specific form setforth herein. Rather, the scope of the present invention is limited onlyby the claims. Additionally, although a feature may appear to bedescribed in connection with particular embodiments, one skilled in theart would recognize that various features of the described embodimentsmay be combined in accordance with the invention.

Furthermore, although individually listed, a plurality of means,elements or method steps may be implemented by, for example, a singleunit or processor. Additionally, although individual features may beincluded in different claims, these may possibly be advantageouslycombined, and the inclusion in different claims does not imply that acombination of features is not feasible and/or advantageous. Also, theinclusion of a feature in one category of claims does not imply alimitation to this category, but rather the feature may be equallyapplicable to other claim categories, as appropriate.

Furthermore, the order of features in the claims does not imply anyspecific order in which the features must be performed and in particularthe order of individual steps in a method claim does not imply that thesteps must be performed in this order. Rather, the steps may beperformed in any suitable order. In addition, singular references do notexclude a plurality. Thus, references to ‘a’, ‘an’, ‘first’, ‘second’,etc. do not preclude a plurality.

What is claimed is:
 1. A wireless network comprising: a first networkelement having an interface configured to communicate with a cluster ofnetwork elements; a processor, of the first network element, configuredto substantially simultaneously multicast a Multicast-Broadcast over aSingle Frequency Network (MBSFN) message to the cluster of networkelements; the first network element is further configured to receive asubscription request, from a second network element, for a multi-cellservice in association with the MBSFN message; the second networkelement configured to send the MBSFN message to a user equipment (UE);and the processor of the first network element is further configured todetermine when to retransmit the MBSFN message, by unicasting ormulticasting, on a condition of not receiving an acknowledgement messagefrom a third network element.
 2. The wireless network of claim 1 whereinmulticasting uses Internet Group Management Protocol (IGMP).
 3. Thewireless network of claim 1 wherein the first network element is furtherconfigured to multicast the MBSFN message using Stream ControlTransmission Protocol (SCTP), Transport Control Protocol (TCP), or UserDatagram Protocol (UDP).
 4. The wireless network of claim 1 wherein thewireless network is configured as a Universal Mobile TelecommunicationsSystem (UMTS) Terrestrial Radio Access Network (UTRAN) or WorldwideInteroperability for Microwave Access (WiMAX) network and the firstnetwork element is configured as a Radio Network Controller (RNC).
 5. Asystem comprising: a first network element having an interfaceconfigured to communicate with a cluster of network elements; aprocessor, of the first network element, configured to substantiallysimultaneously multicast a Multicast-Broadcast over a Single FrequencyNetwork (MBSFN) message to the cluster of network elements; the firstnetwork element is further configured to receive a subscription request,from a second network element, for a multi-cell service in associationwith the MBSFN message; the second network element configured to sendthe MBSFN message to a user equipment (UE); and the processor of thefirst network element is further configured to determine when toretransmit the MBSFN message, by unicasting or multicasting, on acondition of not receiving an acknowledgement message from a thirdnetwork element.
 6. The system of claim 5 wherein the system isconfigured as a Universal Mobile Telecommunications System (UMTS)Terrestrial Radio Access Network (UTRAN) or Worldwide Interoperabilityfor Microwave Access (WiMAX) network and the first network element isconfigured as a Radio Network Controller (RNC).
 7. A method performed bya wireless network, the method comprising: communicating, by a firstnetwork element using an interface, with a cluster of network elements;multicasting, substantially simultaneously by the first network element,a Multicast-Broadcast over a Single Frequency Network (MBSFN) message tothe cluster of network elements; receiving, by the first network elementfrom a second network element, a subscription request for a multi-cellservice in association with the MBSFN message; sending, by the secondnetwork element, the MBSFN message to a user equipment (UE); anddetermining, by the first network element, when to retransmit the MBSFNmessage, by unicasting or multicasting, on a condition of not receivingan acknowledgement message from a third network element.
 8. The methodof claim 7 wherein multicasting uses Internet Group Management Protocol(IGMP).
 9. The method of claim 7 further comprising: multicasting, bythe first network element, the MBSFN message using Stream ControlTransmission Protocol (SCTP), Transport Control Protocol (TCP), or UserDatagram Protocol (UDP).
 10. The method of claim 7 wherein the wirelessnetwork is configured as a Universal Mobile Telecommunications System(UMTS) Terrestrial Radio Access Network (UTRAN) or WorldwideInteroperability for Microwave Access (WiMAX) network and the firstnetwork element is configured as a Radio Network Controller (RNC).
 11. Amethod performed by a system, the method comprising: communicating, by afirst network element using an interface, with a cluster of networkelements; multicasting, substantially simultaneously by the firstnetwork element, a Multicast-Broadcast over a Single Frequency Network(MBSFN) message to the cluster of network elements; receiving, by thefirst network element from a second network element, a subscriptionrequest for a multi-cell service in association with the MBSFN message;sending, by the second network element, the MBSFN message to a userequipment (UE); and determining, by the first network element, when toretransmit the MBSFN message, by unicasting or multicasting, on acondition of not receiving an acknowledgement message from a thirdnetwork element.
 12. The method of claim 11 wherein the system isconfigured as a Universal Mobile Telecommunications System (UMTS)Terrestrial Radio Access Network (UTRAN) or Worldwide Interoperabilityfor Microwave Access (WiMAX) network and the first network element isconfigured as a Radio Network Controller (RNC).